Abstract: Clostridium difficile (CD), parasitic on the intestine, belongs to grampositive bacteria. With the widespread use of antibiotics, the incidence and severity of Clostridium difficile infection  (CDI)  have been on the rise worldwide.  Of  particular note, the emergence and outbreak of virulent ribotype 027 strain (BI/NAP 1/027/toxinⅢ)  has made CD one of the most important healthcare related pathogens.  Researches on CDI epidemiology are undergoing continuous renewal at home and abroad.  The epidemiological situation and risk factors of CDI are reviewed  in order to strengthen the understanding of CDI among clinical medical workers．

Key words: Clostridium , infections；epidemiology；risk factors